MDMA alters fear extinction, and reduces alcohol consumption in inbred alcohol preferring iP rats but not outbred Wistar rats.
Kade L Huckstep, Billi Newton, Grace Bailey, Annai Charlton, Amy J Pearl, Xavier J Maddern, Robyn M Brown, Gavan P Mcnally, Dan I Lubman, Shalini Arunogiri, Kirsten C Morley, Erin J Campbell, Andrew J Lawrence, Leigh C Walker
Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology March 27, 2026 Peer reviewed DOI: 10.1038/s41386-026-02394-2 via PubMed
Summary
MDMA administration before fear extinction reduced alcohol consumption linked to trauma in a rat model, particularly in alcohol-preferring rats. While MDMA decreased freezing behavior during extinction, it did not have lasting effects on recall. The most significant finding was that MDMA prevented an increase in alcohol intake related to shock exposure, but this effect was observed only in genetically predisposed rats. Overall, MDMA showed potential in disrupting the connection between trauma and increased alcohol intake.
Study at a glance
| Design | experimental study |
|---|---|
| Population | inbred alcohol-preferring and outbred Wistar rats of both sexes |
| Key finding | MDMA prevented the shock-related increase in alcohol consumption but only in alcohol-preferring rats. |
Abstract
Comorbidity between post-traumatic stress disorder (PTSD) and alcohol use is common and mutually-reinforcing, yet there are no pharmacological strategies that specifically target trauma-linked escalation of alcohol intake. We evaluated whether 3,4-methylenedioxymethamphetamine (MDMA), given in a therapy-adjunctive fashion (30 min before fear extinction), could facilitate extinction of conditioned fear and reduce alcohol consumption in a rat model that combines fear conditioning, binge-like alcohol access, abstinence, and re-exposure. Inbred alcohol-preferring (iP) and outbred Wistar rats of both sexes underwent auditory fear conditioning, voluntary ethanol drinking, and subsequently fear extinction after MDMA or vehicle administration, with drug-free extinction recall and alcohol consumption assessed thereafter. Fear conditioning increased voluntary alcohol intake only in iP rats, suggesting a genotype-related fear-alcohol contingency. MDMA acutely reduced freezing during extinction, but ultimately reshaped across-session freezing patterns in a strain- and sex-dependent manner. There were no lasting MDMA treatment effects on next-day drug-free recall. MDMA also altered on-drug fear-expression during extinction without affecting later recall in an iP rat cohort without prior alcohol exposure, indicating the effect is not secondary to drinking history. Critically, MDMA prevented the shock-related increase in alcohol consumption but only in iP rats. These data suggest MDMA's most reliable action in this model is to disrupt trauma-linked escalation of alcohol intake in genetically- and experientially- vulnerable rats, rather than to globally enhance fear extinction.